Th1 cytokines in oral lichen planus

Publisher Website
Google Scholar
Abstract
Background: Cell‐mediated immune responses in oral lichen planus (OLP) may be regulated by cytokines and their receptors. Methods: In situ cytokine expression and in vitro cytokine secretion in OLP were determined by immunohistochemistry and ELISA. Results: The majority of subepithelial and intraepithelial mononuclear cells in OLP were CD8+. In some cases, intraepithelial CD8+ cells were adjacent to degenerating keratinocytes. CD4+ cells were observed mainly in the deep lamina propria with occasional CD4+ cells close to basal keratinocytes. Mononuclear cells expressed IFN‐γ in the superficial lamina propria and TNF‐α adjacent to basal keratinocytes. Basal keratinocytes expressed TNF‐α as a continuous band. TNF R1 was expressed by mononuclear cells and basal and suprabasal keratinocytes. There was variable expression of TGF‐β1 in the subepithelial infiltrate while all intraepithelial mononuclear cells were TGF‐β1−. Keratinocytes in OLP stained weakly for TGF‐β1. Unstimulated OLP lesional T cells secreted IFN‐γin vitro. TNF‐α stimulation down‐regulated IFN‐γ secretion and up‐regulated TNF‐α secretion. IL‐4, IL‐10 and TGF‐β1 secretion were not detected. Conclusions: These data suggest the development of a T helper 1 immune response that may promote CD8+ cytotoxic T‐cell activity in OLP.